Why is it important that the primary standard chemical be non-hygroscopic and pure? Why is it important to dry the primary standard to a constant weight?

Answer:

V2 = 17371.43ml

Explanation:

We use Boyles laws

since temperature is constant

P1V1=P2V2

760 x 400 = 17.5 x V2

304000 = 17.5 x V2

V2 = 304000/17.5

V2 = 17371.43ml

The volume will the dry hydrogen gas occupy at the temperature of 20°C and vapor pressure at  760 torrs will be 18 ml.

What is vapor pressure?

The vapor pressure of a liquid is independent of the volume of liquid in the container, whether one liter or thirty liters; both samples will have the same vapor pressure at the same temperature.

The temperature has an exponential connection with vapor pressure, which means that as the temperature rises, the vapor pressure rises as well the equation is -

P1 V1 / T1 = P2 V2 / T1

here, P = pressure

       T = temperature

        V = volume

substituting the value in the equation,

400 ×760 / 20 = 17.5× V / 20

V = 400× 760 / 20 × 17.5 / 20

V = 18 ml

Therefore the volume of the hydrogen gas remaining at this temperature will be 18 ml.

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Answer:

afshkkyfugutuiryfyi

Answer:

O-H stretch signal at 3300 cm-1

Explanation:

In this question, we can start with the reaction mechanism for the synthesis of Nerolin. We have to start with naphthalen-2-ol adding NaOH we can produce the alkoxide. Then this alkoxide can react by an Sn2 reaction with bromomethane to produce Nerolin (see figure 1).

In the starting molecule (naphthalen-2-ol) we have an "OH" group. Therefore we will have an O-H stretch signal around 3300 cm^-1. The alcohol signals are very broad and very intense, so this will be the main signal for the initial molecule. In the final product, we dont have the "OH" therefore this signal will disappear (see figure 2).

I hope it helps!

Answer:

The correct answer is 1.60.

Explanation:

Based on the given question, 25 ml of 0.10 M HCl is titrated with 0.10 M NaOH. Now moles of HCl can be determined by using the formula,  

Moles = volume * concentration of HCl

= 25/1000*0.10 = 0.0025 moles

Similarly the moles of NaOH added will be determined by using the formula,  

Moles of NaOH added = volume * concentration of NaOH

= 15/1000 * 0.10 = 0.0015 moles

The reaction taking place in the given case is,  

HCl + NaOH = NaCl + H2O

Now the moles of excess H+ = moles of excess HCl

= 0.0025 - 0.0015 = 0.001 moles

Based on the given question, the sum of the volume of the solution is 25+15 = 40 ml or 0.040 L

[H+] = moles of H+/total volume

= 0.001 / 0.040 = 0.025 M

pH = -log[H+]

= -log[0.025]  

= 1.60

The pH after 15 ml of NaOH has been volume is 1.60.

It is based on the given question that is, 25 ml of 0.10 M HCl is titrated with 0.10 M NaOH. Now moles of HCl can be specified by using the formula,

Moles is = volume * concentration of HCl

Then is = 25/1000*0.10 = 0.0025 moles

Besides, the moles of NaOH added will be determined by using the formula,

When the Moles of NaOH added is = volume * concentration of NaOH

= 15/1000 * 0.10 = 0.0015 moles

When The reaction taking place in the given case is,

HCl + NaOH = NaCl + H2O

Now the moles of excess H+ = moles of excess HCl

= 0.0025 - 0.0015 = 0.001 moles

Then It Based on the given question, the sum of the volume of the solution is 25+15 = 40 ml or 0.040 L

[H+] = moles of H+/total volume

After that = 0.001 / 0.040 = 0.025 M

pH = -log[H+]

Then = -log[0.025]

Therefore, = 1.60

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Answer:

[tex][OH^-]=0.01165M[/tex]

Explanation:

Hello,

In this case, for the dissociation of methylamine:

[tex]CH_3NH_2(aq)+H_2O(l)\rightleftharpoons CH_3NH_3^+(aq)+OH^-(aq)[/tex]

We can write the basic dissociation constant as:

[tex]Kb=\frac{[CH_3NH_3^+][OH^-]}{[CH_3NH_2]}[/tex]

That in terms of the reaction extent [tex]x[/tex], turns out:

[tex]Kb=\frac{x*x}{[CH_3NH_2]_0-x}[/tex]

[tex]4.4x10^{-4}=\frac{x^2}{0.32M-x}[/tex]

That has the following solution for [tex]x[/tex]:

[tex]x_1=-0.01209M\\x_2=0.01165M[/tex]

Yer 0.01165M is valid only as no negative concentrations are eligible. It means that it is the concentration of hydroxyl ions in the solution:

[tex][OH^-]=0.01165M[/tex]

Best regards.

Answer:

Explanation:

The subscripts in a formula determine the ratio of the moles of each element in the compound. To convert this formula to the empirical formula, divide each subscript by 2. This is similar to reducing a fraction to its lowest denominator.

Answer:

[tex]Sc_2O_3[/tex] reacts with an acidic solution

Explanation:

Scandium Oxide [tex]Sc_2O_3[/tex] is a basic metal oxide which therefore reacts with acidic solution. An oxide is  a compound that contains only two elements, one of which is oxygen .

The objective of this question is to Write a balanced chemical equation to support your answer.

The chemical equation to support the reaction of [tex]Sc_2O_3[/tex] with acidic solution is as follows:

Assuming the acidic solution to be HCl

[tex]\mathbf{Sc_2O_3_{(s)} + 6 HCl_{(aq)} ----> 2 ScCl_{3(aq)} + 3H_2O_{(l)}}[/tex]

The ionic equation :

[tex]\mathbf{Sc_2O_{3(s)} + 6H^+_{(aq)} ---> 2Sc^{3+}_{(aq)} + 3H_2O_{(l)}}[/tex]

Answer:

131.29 kJ

Explanation:

Let's consider the following balanced equation.

H₂O(g) + C(graphite)(s)  ⇄ H₂(g) + CO(g)

Given the standard enthalpies of formation (ΔH°f), we can calculate the standard enthalpy change for the reaction (ΔH°r) using the following expression.

ΔH°r = 1 mol × ΔH°f(H₂(g)) + 1 mol × ΔH°f(CO(g)) - 1 mol × ΔH°f(H₂O(g)) - 1 mol × ΔH°f(C(graphite)(s))

ΔH°r = 1 mol × (0 kJ/mol) + 1 mol × (-110.53 kJ/mol) - 1 mol × (-241.82 kJ/mol) - 1 mol × (0 kJ/mol)

ΔH°r = 131.29 kJ

Answer:

gaining two electrons

Explanation:

electron configuration

2:6

so add two to 6 to get stable 2:8

Answer:

0.250 mol Mg²⁺

0.500 mol Cl⁻

Explanation:

Magnesium chloride (MgCl₂) dissociates into ions according to the following equilibrium:

MgCl₂  ⇒  Mg²⁺ + 2 Cl⁻

1 mol      1 mol   2 mol

1 mol of Mg²⁺ and 2 moles of Cl⁻ are formed per mole of MgCl₂.  If we have 0.250 mol of MgCl₂, the following amounts of ions will be formed:

0.250 mol MgCl₂ x 1 mol Mg²⁺/mol MgCl₂= 0.250 mol Mg²⁺

0.250 mol MgCl₂ x 2 mol Cl⁻/mol MgCl₂= 0.500 mol Cl⁻

Answer:

HEY THE ANSWER ABOVE ME IS RIGHT!! i defientely misclicked my rating :/

5/5 all the way.

Explanation:

Answer:

The mass of NaHCO3 required is 235.22 g

Explanation:

*******

Continuation of Question:

2NaHCO3(s) + H2SO4(aq)  →  Na2SO4(aq) + 2CO2(g) + 2H2O(l)

You estimate that your acid spill contains about 1.4 mol H2SO4. What mass of NaHCO3 do you need to neutralize the acid?

********\

The question requires us to calculate the mass of NaHCO3  to neutralize the acid.

From the balanced chemical equation;

1 mol of H2SO4 requires 2 mol of NaHCO3

1.4 would require x?

Upon solving for x we have;

x = 1.4 * 2 = 2.8 mol of NaHCO3

The relationship between mass and number of moles is given as;

Mass = Number of moles * Molar mass

Mass = 2.8 mol * 84.007 g/mol

Mass =  235.22 g

Answer:

3.383x10⁻³ micromoles of HgCl

Explanation:

The chemist adds 170mL of a 1.99x10⁻⁵mmol/L Mercury (I) chloride, HgCl.

The solution contains 1.99x10⁻⁵milimoles of HgCl in 1L. That means in 170mL = 0.170L there are:

0.170L × (1.99x10⁻⁵milimoles HgCl / L) = 3.383x10⁻⁶ milimoles of HgCl.

Now, in 1milimole you have 1000 micromoles. That means in 3.383x10⁻⁶ milimoles of HgCl you have:

3.383x10⁻⁶ milimoles of HgCl ₓ (1000micromoles / 1milimole) =

double displacement

bcoz each of the reactants combines with other reactants to obtain the product

Answer:

Molarity Cu²⁺ = 0.423M Cu²⁺

Explanation:

40.8g of copper (II) acetate into 200mL of a 0.700M sodium chromate

The reaction of copper acetate with sodium chromate occurs as follows:

Cu(CH₃COO)₂(aq) + Na₂CrO₄(aq) → CuCrO₄(s) + 2CH₃COONa

In water, the Copper(II) acetate dissociates in Cu²⁺ cation.

To know final molarity of Cu²⁺ we need to calculate the moles of Cu²⁺ that don't react with chromate ion, thus:

Moles of 40.8g of copper(II) acetate (Molar mass: 181.63g/mol) are:

40.8g × (1mol / 181.63g) = 0.2246 moles of Copper(II) acetate

Moles of sodium chromate are:

0.200L ₓ (0.700mol / L) = 0.140 moles of sodium chromate.

As 1 mole of Copper(II) acetate reacts per mole of sodium chromate, moles of Copper(II) acetate = Moles of Cu²⁺ that remains after the reaction are:

0.2246mol - 0.140moles = 0.0846 moles of Cu²⁺

Molarity is ratio between moles of solute (Moles Cu²⁺) and volume in liters of solution (200mL = 0.200L):

Molarity Cu²⁺ = 0.0846 moles / 0.200L

Answer:

0.0590 M⁻¹

Explanation:

Kc represents the equilibrium constant. It is given as;

Kc = [products] / [reactants]

For the reaction; 2SO2(g) + O2(g) <--> 2SO3

Products = SO3

Reactants = SO2 and O2

Kc is given as;

Kc = [SO3]² / [SO2]² [O2]

Kc = 0.120² / (0.860)² (0.330)

Kc = 0.0144 / 0.2440 = 0.0590 M⁻¹

Answer:

A. copper is highly water soluble. It will turn into 5 different hydrates as it absorbs more and more water.

b. Glycerol is easily soluble in water, due to the ability of the polyol groups to form hydrogen bonds with water molecules

c. octane is considered to be non-polar, it will not be soluble in water, since water is a polar solvent. This will happen because octane (hydrocarbons in general) contains neither ionic groups, nor polar functional groups that can interact with water molecules.

d. Nitric acid decomposes into water, nitrogen dioxide, and oxygen, forming a brownish yellow solution.

e. Barium carbonate is a white powder. It is insoluble in water and soluble in most acids

Explanation:

Answer:

B

Explanation:

The alkaline earth metals are the elements located in Group 2. The only element out of our choices that is in Group 2 is Magnesium.

Answer:

592 K or 319° C

Explanation:

From the statement of Charles law we know that the volume of a given mass of gas is directly proportional to its absolute temperature at constant pressure. Thus;

V1/T1= V2/T2

Initial volume V1 = 1.75 L

Initial temperature T1= 23.0 +273 = 296 K

Final volume V2= 3.50 L

Final temperature T2 = the unknown

T2= V2T1/V1= 3.50 × 296 / 1.75

T2 = 592 K or 319° C

Answer:

The pressure the gas will have if the pressure is initially 1.50 atm at 22.0 ° C and the temperature changes at 11.0 ° C is 1.44 atm (option D)

Explanation:

Gay Lussac's law indicates that, as long as the volume of the container containing the gas is constant, as the temperature increases, the gas molecules move more rapidly. Then the number of collisions against the walls increases, that is, the pressure increases. That is, the gas pressure is directly proportional to its temperature.

Gay-Lussac's law can be expressed mathematically as follows:

[tex]\frac{P}{T}=k[/tex]

Where P = pressure, T = temperature, K = Constant

You have a gas that is at a pressure P1 and at a temperature T1. When the temperature varies to a new T2 value, then the pressure will change to P2, and then:

[tex]\frac{P1}{T1}=\frac{P2}{T2}[/tex]

In this case:

Replacing:

[tex]\frac{1.5 atm}{295 K}=\frac{P2}{284 K}[/tex]

Solving:

[tex]P2= 284 K*\frac{1.5 atm}{295 K}[/tex]

P2=1.44 atm

The pressure the gas will have if the pressure is initially 1.50 atm at 22.0 ° C and the temperature changes at 11.0 ° C is 1.44 atm (option D)

Answer:

Q = 246 kJ

Explanation:

It is given that,

Mass of water, m = 200 g

Let initial temperature, [tex]T_i=5^{\circ}[/tex]

Final temperature of water, [tex]T_f=300^{\circ} C[/tex]

We know that the specific heat capacity of water, [tex]c=4.18\ J/g-^{\circ} C[/tex]

So, the heat energy needed to raise the temperature is given by :

[tex]Q=mc\Delta T\\\\Q=200\times 4.18\times (300-5)\\\\Q=246620\ J[/tex]

or

Q = 246 kJ

So, the heat energy of 246 kJ is needed.

Answer:

e. Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g)

Explanation:

All the following are oxidation–reduction reactions except:________

a. H₂(g) + F₂(g) → 2HF(g).  Redox. H is oxidized and F is reduced.

b. Ca(s) + H₂(g) → CaH₂(s).  Redox. Ca is oxidized and H is reduced.

c. 2K(s) + 2H₂O(l) → 2KOH(aq) + H₂(g).  Redox. K is oxidized and H is reduced.

d. 6Li(s) + N₂(g) → 2Li₃N(s).  Redox. Li is oxidized and N is reduced.

e. Mg₃N₂(s) + 6H₂O(l) → 3Mg(OH)₂(s) + 2NH₃(g). Not redox. All the elements have the same oxidation number

The reaction Mg3N2(s) + 6H2O(l) → 3Mg(OH)2(s) + 2NH3(g) is not a redox reaction.

Redox reactions are those reactions in which there is a change in the oxidation number of species from left to right in the reaction. A specie is oxidized leading to increase in oxidation number while another specie is reduced leading to decrease in oxidation number.

The reaction in which there is no change in oxidation number of species from left to right is the reaction; Mg3N2(s) + 6H2O(l) → 3Mg(OH)2(s) + 2NH3(g).

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Answer:

Here's what I get  

Explanation:

pKₐ of o-vanillin = 7.81; pKₐ of p-toluidine = 4.44

The higher the pKₐ, the weaker the acid.

Thus, o-vanillin is the weaker acid and has a stronger conjugate base.

The conjugate acid of p-toluidine is the stronger and has the weaker conjugate base.

The equation for the equilibrium is

H-OC₆H₃(OCH₃)CHO + CH₃C₆H₄NH₂ ⇌ ⁻OC₆H₃(OCH₃)CHO + CH₃C₆H₄NH₃⁺

    weaker acid              weaker base          stronger  base        stronger acid

The reaction between the stronger acid and the stronger base pushes the position of equilibrium to the left.

Thus, o-vanillin does not fully protonate p-toluidine.

O-vanillin is a weaker acid than p-toluidine and has a more stable conjugate base; hence, o-vanillin does not fully protonate p-toluidine.

The pKa is defined as the negative logarithm of Ka. The dissociation constant of an acid Ka shows the extent of dissociation of an acid in solution. The higher the pKa, the lower the Ka and the weaker the acid.

The pKₐ of o-vanillin is 7.81 while the pKₐ of p-toluidine is 4.44. This means that  o-vanillin is a weaker acid than p-toluidine and has a more stable conjugate base. Hence, o-vanillin does not fully protonate p-toluidine.

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Answer:

DE2

Explanation: for every one D+2 you need two E-1 because +2=-2

Answer:

Complex I:  (1) NADH-ubiquinone(NADH-coenzyme Q oxidoreductase), (8) Electron transfer from NADH to ubiquinone (coenzyme Q)

Complex II:  (3) Electron transfer from succinate to ubiquinone (coenzyme Q) (5) Succinate-coenzyme Q Oxidoreductase (succinate dehydrogenase)

Complex III:  (2) Coenzyme Q-cytochrome c oxidoreductase, (7) Electron transfer from ubiquinol (QH2) to cytochrome c

Complex IV: (4) Electron transfer from cytochrome c to O2, (6) Cytochrome c oxidase

Explanation:

The electron transport chain (ETC) in the mitochondria provides a pathway by which electrons are transferred from NADH and FADH₂ through a series of membrane-bound carriers to  molecular oxygen reducing it to water.

The electron transport chain electron carriers are organized into four complexes, Complexes I - IV.

Complex I : It is also called NADH:ubiquinone reductase. It transfers electrons from NADH to ubiquinone (also known as coenzyme Q)

Complex II : It is also called succinate dehydrogenase. It functions to tranfer electrons from succinate to FAD and then to ubiquinone.

Complex III : It is also called ubiquinone:cytochrome c oxidoreductase. It functions to transfer electrons from ubiquinol (reduced ubiquinone) to cytochrome c.

Complex IV : It is also called cytochrome oxidase. It functions to transfer electrons from cytochrome c to molecular oxygen reducing it to water.

The electron transporter chain is a series of enzymatic reactions to produce and store energy for the organism’s correct functioning. Complex I: 1 and 8. Complex II: 3 and 5. Complex III: 2 and 7. Complex IV: 4 and 6.

---------------------------------

Electron transporter chain

The electron transporter chain is located in the internal mitochondrial membrane. It constitutes a series of enzymatic reactions to release and save energy for the organism’s correct functioning.  

Along the chain, there are four proteinic complexes in the membrane, I, II, III, and IV, that contain the electrons transporters and the enzymes necessary to catalyze the electrons' transference from one complex to the other.  

Different redox reactions occur to pass electrons along the chain.  

Released energy creates a proton concentration gradient used to synthesize ATP.  

1)  NADH provides electrons to the first complex, Complex I (NADH-  

   ubiquinone or NADH-coenzyme Q oxidoreductase).

From there, electrons go to the coenzyme Q (Ubiquinone) that carries them to complex II and III. Meanwhile, complex I pomp four protons to the intermembrane space.  

2) Complex II (succinate-dehydrogenase) receives electrons from CoQ and also receives electrons from FADH2. Electrons are sent from complex II to ubiquinone Q that carries these electrons to complex III.

3) Complex III (Cytochrome C-reductase) receives electrons from ubiquinone Q and pomps protons to the intermembrane space.

Electrons are transferred to Cytochrome c.  

Electrons travel from cytochrome c to complex IV.

4) Complex IV (Cytochrome C-oxidase)  is the last complex that pomps protons to the intermembrane space. It takes electrons from cytochrome C and sends them to oxygen.

5) Electrons are sent to O₂ molecules, which also receive protons in the matrix to create water molecules.

Four electrons are needed to produce two water molecules from one O₂ molecule.  

The proton gradient is used to produce ATP molecules.

Now, we can join the complexes with the phrases.

Complex I:

1) NADH-ubiquinone (NADH-coenzyme Q oxidoreductase)

8) Electron transfer from NADH to ubiquinone (coenzyme Q)

Complex II:

3) Electron transfer from succinate to ubiquinone (coenzyme Q)

5) Succinate-coenzyme Q Oxidoreductase (succinate dehydrogenase)

Complex III:

2) Coenzyme Q - cytochrome c oxidoreductase

7) Electron transfer from ubiquinol (QH₂) to cytochrom c

Complex IV:

6) Cytochrome C oxidase

4) Electron transfer from cytochrome c to O₂

-----------------------------------

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Answer:

V2 = 4.48L

Explanation:

using charles law

V1/T1=V2/T2

3.4/283=V2/373

0.012=V2/373

V2= 0.012 x 373

V2 = 4.48L

Answer:

53.1% of hydrogen reacts

Explanation:

The mixture of 2 atoms of H with 1 atom of O produce 1 molecule of H₂.

The mass of hydrogen in 2.32g of H₂O could be obtained using molar mass of H₂O (18.01g/mol) and molar mass of hydrogen (1.01g/mol) as follows:

Moles H₂O: 2.32g H₂O × (1mole / 18.01g) = 0.1288 moles of water

1 mole of H₂O contains 2 moles of H, moles of hydrogen in 0.1288 moles of water are:

0.1288 moles H₂O × (2 moles H / 1 mole H₂O) = 0.2576 moles of H

In mass:

0.2576 moles H × (1.01g/ mol H) = 0.260g H you have in the formed water

As before reaction you had 0.485g of H and just 0.260g reacted, mass percent is:

(Mass that reacts / Mass added) × 100

(0.260g / 0.485g) × 100 =

Answer:

[tex]FADH_2+Q --> FAD + QH_2[/tex]

The reactant that is reduced is Q.

Explanation:

The complete equation for the reaction is such that:

[tex]FADH_2+Q --> FAD + QH_2[/tex]

Two molecules of H atom is lost from [tex]FADH_2[/tex] and the H atoms are gained by the coenzyme Q. Consequently,  [tex]FADH_2[/tex] becomes FAD while Q becomes [tex]QH_2[/tex].

From the definition of oxidation as loss of hydrogen and reduction as the addition of hydrogen, it can be concluded that the FADH2 that lost hydrogen is a reactant that is oxidized while the coenzyme Q that gained hydrogen is a reactant that is reduced in the reaction.

Answer:

The heat absorbed by the sample of water is 3,294.9 J

Explanation:

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

The sensible heat of a body is the amount of heat received or transferred by a body when it undergoes a temperature variation (Δt) without there being a change of physical state (solid, liquid or gaseous). Its mathematical expression is:

Q = c * m * ΔT

Where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.

In this case:

Replacing:

Q= 4.184 [tex]\frac{J}{g*C}[/tex] * 45 g* 17.5 C

Solving:

Q=3,294.9 J

The heat absorbed by the sample of water is 3,294.9 J

Answer: E = - 19.611×[tex]10^{-18}[/tex] J

Explanation: The lowest possible energy can be calculated using the formula:

[tex]E_{n} = - Z^{2}.\frac{k}{n^{2}}[/tex]

where:

Z is atomic number of the atom;

k is a constant which contains other constants and is 2.179×[tex]10^{-18}[/tex] J

n is a layer;

For the lowest possible, n=1.

Atom of Lithium has atomic number of Z=3

Substituing:

[tex]E_{1} = - 3^{2}.\frac{2.179.10^{-18}}{1}[/tex]

[tex]E_{1} =[/tex] [tex]-19.611.10^{-18}[/tex] J

The energy for the electron in the [tex]Li^{+2}[/tex] ion is - 19.611 joules

The lowest possible energy, in Joules, for the electron in the [tex]Li^{2+}[/tex] ion is equal to [tex]1.96\times 10^{-17}\; Joules[/tex]

To determine the lowest possible energy, in Joules, for the electron in the [tex]Li^{2+}[/tex] ion, we would use the Bohr model:

Mathematically, Bohr's model is given by the equation:

[tex]Energy = -Z^2 \frac{k}{n^2}[/tex]

Where:

We know that the atomic number of lithium (Li) is equal to 3.

Also, at the lowest possible energy, n = 1.

Rydberg constant = [tex]2.179 \times 10^{-18}[/tex]

Substituting the parameters into the equation, we have;

[tex]E_1 = -3^2 \times \frac{2.179 \times 10^{-18}}{1^2} \\\\E_1 =9 \times 2.179 \times 10^{-18}\\\\E_1 =1.96\times 10^{-17}\; Joules[/tex]

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Answer:

19.07 g mol^-1

Explanation:

The computation of the molecular mass of the unknown gas is shown below:

As we know that

[tex]\frac{Diffusion\ rate\ of unknown\ gas }{CO_{2}\ diffusion\ rate} = \frac{\sqrt{CO_{2\ molar\ mass}} }{\sqrt{Unknown\ gas\ molercular\ mass } }[/tex]

where,

Diffusion rate of unknown gas = 155 mL/s

CO_2 diffusion rate = 102 mL/s

CO_2 molar mass = 44 g mol^-1

Unknown gas molercualr mass = M_unknown

Now placing these values to the above formula

[tex]\frac{155mL/s}{102mL/s} = \frac{\sqrt{44 g mol^{-1}} }{\sqrt{M_{unknown}} } \\\\ 1.519 = \frac{\sqrt{44 g mol^{-1}} }{\sqrt{M_{unknown}} } \\\\ {\sqrt{M_{unknown}} } = \frac{\sqrt{44 g mol^{-1}}}{1.519} \\\\ {\sqrt{M_{unknown}} } = \frac{44 g mol^{-1}}{(1.519)^{2}}[/tex]

After solving this, the molecular mass of the unknown gas is

= 19.07 g mol^-1